BSD Router Project

This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.
====== Multicast with PIM-DM ======

This lab show a multicast routing example using PIM Dense Mode.

<note warning>
pimdd is broken: Need to Debug it one day
</note>
===== Presentation =====

==== Network diagram ====

Here is the logical and physical view:

{{:documentation:examples:labs.multicast-pim-dm.png|}}

===== Setting-up the lab =====

==== Downloading BSD Router Project images ====

Download BSDRP serial image (prevent to have to use an X display) on Sourceforge.

==== Download Lab scripts =====

More information on these BSDRP lab scripts available on [[documentation:examples:How to build a BSDRP router lab]].

Start the lab with 4 routers using emulated e1000 NIC (vtnet interfaces didn't support multicast-routing on FreeBSD):
<code>
tools/BSDRP-lab-bhyve.sh -i /usr/obj/BSDRP.amd64/BSDRP-1.702-full-amd64-serial.img.xz -n 4 -e
BSD Router Project (http://bsdrp.net) - bhyve full-meshed lab script
Setting-up a virtual lab with 4 VM(s):
- Working directory: /tmp/BSDRP
- Each VM have 1 core(s) and 256M RAM
- Emulated NIC: e1000
- Switch mode: bridge + tap
- 0 LAN(s) between all VM
- Full mesh Ethernet links between each VM
VM 1 have the following NIC:
- em0 connected to VM 2
- em1 connected to VM 3
- em2 connected to VM 4
VM 2 have the following NIC:
- em0 connected to VM 1
- em1 connected to VM 3
- em2 connected to VM 4
VM 3 have the following NIC:
- em0 connected to VM 1
- em1 connected to VM 2
- em2 connected to VM 4
VM 4 have the following NIC:
- em0 connected to VM 1
- em1 connected to VM 2
- em2 connected to VM 3
For connecting to VM'serial console, you can use:
- VM 1 : cu -l /dev/nmdm1B
- VM 2 : cu -l /dev/nmdm2B
- VM 3 : cu -l /dev/nmdm3B
- VM 4 : cu -l /dev/nmdm4B
</code>

===== Routers configuration =====

==== Router 1 ====

Configurating, applying changes and saving configuration:
<code>
sysrc hostname=VM1 \
 gateway_enable=no \
 ipv6_gateway_enable=no \
 ifconfig_em0="inet 10.0.12.1/24" \
 defaultrouter=10.0.12.254
hostname VM1
service netif restart
service routing restart
config save
</code>
==== Router 2 ====

<code>
sysrc hostname=VM2 \
 ifconfig_em0="inet 10.0.12.254/24" \
 ifconfig_em1="inet 10.0.23.2/24" \
 defaultrouter=10.0.23.3 \
 pimdd_enable=yes
cp /usr/local/etc/pimdd.conf.sample /usr/local/etc/pimd.conf
hostname VM2
service netif restart
service routing restart
service pimdd start
config save
</code>
==== Router 3 ====

<code>
sysrc hostname=VM3 \
 ifconfig_em1="inet 10.0.23.3/24" \
 ifconfig_em2="inet 10.0.34.254/24" \
 defaultrouter=10.0.23.2 \
 pimdd_enable=yes
cp /usr/local/etc/pimdd.conf.sample /usr/local/etc/pimd.conf
hostname VM3
service netif restart
service routing restart
service pimdd start
config save
</code>
==== Router 4 ====

<code>
sysrc hostname=VM4 \
 gateway_enable=no \
 ipv6_gateway_enable=no \
 ifconfig_em2="inet 10.0.34.4/24" \
 defaultrouter=10.0.34.254
hostname VM4
service netif restart
service routing restart
config save
</code>

===== Checking pimdd behavior =====

==== Generating VIF ====

Does the pimdd had correctly generated VIF ?

<code>
[root@R2]~# netstat -g

IPv4 Virtual Interface Table
 Vif   Thresh   Local-Address   Remote-Address    Pkts-In   Pkts-Out
  0         1   10.0.12.2                               0          0
  1         1   10.0.23.2                               0          0

IPv4 Multicast Forwarding Table is empty


IPv6 Multicast Interface Table is empty

IPv6 Multicast Forwarding Table is empty
</code>

<code>
[root@R3]~# netstat -g

IPv4 Virtual Interface Table
 Vif   Thresh   Local-Address   Remote-Address    Pkts-In   Pkts-Out
  0         1   10.0.23.3                               0          0
  1         1   10.0.34.3                               0          0

IPv4 Multicast Forwarding Table is empty


IPv6 Multicast Interface Table is empty

IPv6 Multicast Forwarding Table is empty
</code>

=> There are VIF for all PIM-DM enabled interface

==== Does PIM daemon locally register to PIM mcast group ? ====

PIM router need to register to 224.0.0.13 mcast group, check if all PIM routers correctly display this group on their enabled interfaces:

<code>
[root@R2]~# ifmcstat
em0:
        inet 10.0.12.2
        igmpv2
                group 224.0.0.2 mode exclude
                        mcast-macaddr 01:00:5e:00:00:02
                group 224.0.0.13 mode exclude
                        mcast-macaddr 01:00:5e:00:00:0d
        inet6 fe80::a8aa:ff:fe00:212%em0 scopeid 0x1
        mldv2 flags=2<USEALLOW> rv 2 qi 125 qri 10 uri 3
                group ff01::1%em0 scopeid 0x1 mode exclude
                        mcast-macaddr 33:33:00:00:00:01
                group ff02::2:1124:9296%em0 scopeid 0x1 mode exclude
                        mcast-macaddr 33:33:11:24:92:96
                group ff02::2:ff11:2492%em0 scopeid 0x1 mode exclude
                        mcast-macaddr 33:33:ff:11:24:92
                group ff02::1%em0 scopeid 0x1 mode exclude
                        mcast-macaddr 33:33:00:00:00:01
                group ff02::1:ff00:212%em0 scopeid 0x1 mode exclude
                        mcast-macaddr 33:33:ff:00:02:12
        inet 10.0.12.2
        igmpv2
                group 224.0.0.1 mode exclude
                        mcast-macaddr 01:00:5e:00:00:01
em1:
        inet 10.0.23.2
        igmpv2
                group 224.0.0.2 mode exclude
                        mcast-macaddr 01:00:5e:00:00:02
                group 224.0.0.13 mode exclude
                        mcast-macaddr 01:00:5e:00:00:0d
        inet6 fe80::a8aa:ff:fe02:202%em1 scopeid 0x2
        mldv2 flags=2<USEALLOW> rv 2 qi 125 qri 10 uri 3
                group ff01::1%em1 scopeid 0x2 mode exclude
                        mcast-macaddr 33:33:00:00:00:01
                group ff02::2:1124:9296%em1 scopeid 0x2 mode exclude
                        mcast-macaddr 33:33:11:24:92:96
                group ff02::2:ff11:2492%em1 scopeid 0x2 mode exclude
                        mcast-macaddr 33:33:ff:11:24:92
                group ff02::1%em1 scopeid 0x2 mode exclude
                        mcast-macaddr 33:33:00:00:00:01
                group ff02::1:ff02:202%em1 scopeid 0x2 mode exclude
                        mcast-macaddr 33:33:ff:02:02:02
        inet 10.0.23.2
        igmpv2
                group 224.0.0.1 mode exclude
                        mcast-macaddr 01:00:5e:00:00:01
</code>

<code>
[root@R3]~# ifmcstat
em1:
        inet 10.0.23.3
        igmpv2
                group 224.0.0.2 mode exclude
                        mcast-macaddr 01:00:5e:00:00:02
                group 224.0.0.13 mode exclude
                        mcast-macaddr 01:00:5e:00:00:0d
        inet6 fe80::a8aa:ff:fe00:323%em1 scopeid 0x2
        mldv2 flags=2<USEALLOW> rv 2 qi 125 qri 10 uri 3
                group ff01::1%em1 scopeid 0x2 mode exclude
                        mcast-macaddr 33:33:00:00:00:01
                group ff02::2:1124:9296%em1 scopeid 0x2 mode exclude
                        mcast-macaddr 33:33:11:24:92:96
                group ff02::2:ff11:2492%em1 scopeid 0x2 mode exclude
                        mcast-macaddr 33:33:ff:11:24:92
                group ff02::1%em1 scopeid 0x2 mode exclude
                        mcast-macaddr 33:33:00:00:00:01
                group ff02::1:ff00:323%em1 scopeid 0x2 mode exclude
                        mcast-macaddr 33:33:ff:00:03:23
        inet 10.0.23.3
        igmpv2
                group 224.0.0.1 mode exclude
                        mcast-macaddr 01:00:5e:00:00:01
em2:
        inet 10.0.34.3
        igmpv2
                group 224.0.0.2 mode exclude
                        mcast-macaddr 01:00:5e:00:00:02
                group 224.0.0.13 mode exclude
                        mcast-macaddr 01:00:5e:00:00:0d
        inet6 fe80::a8aa:ff:fe03:303%em2 scopeid 0x3
        mldv2 flags=2<USEALLOW> rv 2 qi 125 qri 10 uri 3
                group ff01::1%em2 scopeid 0x3 mode exclude
                        mcast-macaddr 33:33:00:00:00:01
                group ff02::2:1124:9296%em2 scopeid 0x3 mode exclude
                        mcast-macaddr 33:33:11:24:92:96
                group ff02::2:ff11:2492%em2 scopeid 0x3 mode exclude
                        mcast-macaddr 33:33:ff:11:24:92
                group ff02::1%em2 scopeid 0x3 mode exclude
                        mcast-macaddr 33:33:00:00:00:01
                group ff02::1:ff03:303%em2 scopeid 0x3 mode exclude
                        mcast-macaddr 33:33:ff:03:03:03
        inet 10.0.34.3
        igmpv2
                group 224.0.0.1 mode exclude
                        mcast-macaddr 01:00:5e:00:00:01
</code>

We correctly sees mcast group 224.0.0.13 subscribed on PIM enabled interfaces.

===== Testing =====

==== Enable IPerf server on R4 (mcast receiver) ====

This IPerf server will listen the 239.1.1.1 multicast group
<code>
[root@R4]~# iperf -s -u -B 239.1.1.1 -i 1
------------------------------------------------------------
Server listening on UDP port 5001
Binding to local address 239.1.1.1
Joining multicast group  239.1.1.1
Receiving 1470 byte datagrams
UDP buffer size: 41.1 KByte (default)
------------------------------------------------------------

</code>


==== IPerf client on R1 (mcast sender) ====

Start an iperf client to 239.1.1.1.

<code>
[root@R1]~# iperf -c 239.1.1.1 -u -T 32 -t 300 -i 1
------------------------------------------------------------
Client connecting to 239.1.1.1, UDP port 5001
Sending 1470 byte datagrams
Setting multicast TTL to 32
UDP buffer size: 9.00 KByte (default)
------------------------------------------------------------
[  3] local 10.0.12.1 port 34390 connected with 239.1.1.1 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0- 1.0 sec   128 KBytes  1.05 Mbits/sec
[  3]  1.0- 2.0 sec   128 KBytes  1.05 Mbits/sec
[  3]  2.0- 3.0 sec   128 KBytes  1.05 Mbits/sec
[  3]  0.0- 3.0 sec   385 KBytes  1.05 Mbits/sec
[  3] Sent 268 datagrams
</code>

Now check than R4 receive the iperf trafic send by R1:

<code>
Nothing !?
</code>

==== Troubleshooting ====

=== Multicast table on R2 ===

What's the status of multicast table of the first router:
<code>
[root@router]~# netstat -g

IPv4 Virtual Interface Table
 Vif   Thresh   Local-Address   Remote-Address    Pkts-In   Pkts-Out
  0         1   10.0.12.2                            2799          0
  1         1   10.0.23.2                               0          0

IPv4 Multicast Forwarding Table
 Origin          Group             Packets In-Vif  Out-Vifs:Ttls
 10.0.12.1       239.1.1.1            2799    0


IPv6 Multicast Interface Table is empty

IPv6 Multicast Forwarding Table is empty
</code>

=> it correctly detect a multicast source comming from VIF 0 (em0) but didn't forward packet toward R3: Why ?

=== Using R3 as a subscriber ===

Starting an iperf receiver on R3 and check if it received mcast traffic by re-starting ipferf on R1.

Status of mcast routing table on R2:

<code>
[root@R2]~# netstat -g

IPv4 Virtual Interface Table
 Vif   Thresh   Local-Address   Remote-Address    Pkts-In   Pkts-Out
  0         1   10.0.12.2                            5516          0
  1         1   10.0.23.2                               0        162

IPv4 Multicast Forwarding Table
 Origin          Group             Packets In-Vif  Out-Vifs:Ttls
 10.0.12.1       239.1.1.1             162    0    1:1


IPv6 Multicast Interface Table is empty

IPv6 Multicast Forwarding Table is empty
</code>

=> R2 correctly received AND forward mcast traffic from VIF0 (em0) to VIF1 (em1)

and R3 correctly receive mcast traffic:
<code>
------------------------------------------------------------
[  3] local 239.1.1.1 port 5001 connected with 10.0.12.1 port 11166
[ ID] Interval       Transfer     Bandwidth        Jitter   Lost/Total Datagrams
[  3]  0.0- 1.0 sec   128 KBytes  1.05 Mbits/sec   0.175 ms    0/   89 (0%)
[  3]  1.0- 2.0 sec   128 KBytes  1.05 Mbits/sec   0.251 ms    0/   89 (0%)
[  3]  2.0- 3.0 sec   128 KBytes  1.05 Mbits/sec   0.189 ms    0/   89 (0%)
[  3]  3.0- 4.0 sec   128 KBytes  1.05 Mbits/sec   0.165 ms    0/   89 (0%)
[  3]  4.0- 5.0 sec   128 KBytes  1.05 Mbits/sec   0.268 ms    0/   89 (0%)
[  3]  5.0- 6.0 sec   128 KBytes  1.05 Mbits/sec   0.243 ms    0/   89 (0%)
[  3]  6.0- 7.0 sec   129 KBytes  1.06 Mbits/sec   0.199 ms    0/   90 (0%)
[  3]  7.0- 8.0 sec   128 KBytes  1.05 Mbits/sec   0.187 ms    0/   89 (0%)
</code>

=> Need to found why R2 didn't forward traffic to a next-hop-PIM router.

To dig, error on R2 pimd daemon:
<code>
Jun  7 09:22:48 router pimdd[1483]: warning - sendto from 10.0.12.2 to 224.0.0.13: Invalid argument
Jun  7 09:22:48 router pimdd[1483]: warning - sendto from 10.0.23.2 to 224.0.0.13: Invalid argument
Jun  7 09:23:07 router pimdd[1483]: warning - received packet from 10.0.23.3 shorter (48 bytes) than hdr+data length (24+12264)
Jun  7 09:23:07 router pimdd[1483]: warning - received packet from 10.0.23.3 shorter (48 bytes) than hdr+data length (24+12264)
Jun  7 09:23:17 router pimdd[1483]: warning - sendto from 10.0.12.2 to 224.0.0.13: Invalid argument
Jun  7 09:23:17 router pimdd[1483]: warning - sendto from 10.0.23.2 to 224.0.0.13: Invalid argument
</code>

This problem is linked to the [[https://wiki.freebsd.org/SOCK_RAW|FreeBSD SOCK_RAW recent changes]].